Fallen leaves should be removed from a lawn soon after they fall, both for aesthetics and for the health of the lawn. Delaying their removal allows dew and rain on the fallen leaves to hasten their partial decomposition, which exacerbates their removal. There are broadly two ways to remove leaves and other debris from lawns: vacuuming or mechanically impelling leaves into a transportable receptacle, and blowing or raking the leaves to a storage location. This invention relates to the former.
Manually operated rakes are known, however they are expensive in human time consumed. Automated rakes are known, such as the rotary rake in U.S. Pat. No. 333,917. Air blowers in a variety of configurations improve the rate of leaf herding over manual rakes, however they are generally energetically inefficient.
Exergy, or thermodynamic availability, is energy available from the immediate environment. As energy costs rise, it is preferable for appliances such as leaf herders to be exergetically powered, for example from solar power. Solar powered vehicles are known, such as the Mars Rover; functions in addition to locomotion performed by solar powered vehicles generally need to be engineered for low average power consumption.